Information Encapsulation is the aggregation of information that belongs together and can be implemented at different states of the information life cycle. For Digital Preservation this usually means pairing a digital object with its metadata. The PeriCAT open-source tool provides encapsulation techniques and mechanisms that help ensure the information remains accessible even if the digital object leaves its creation environment. The tool supports the creation of self-describing objects and the long-term reusability of information.
The two main categories: Information Embedding and Packaging. Packaging refers to the aggregation information, like files or streams, as equal entities stored in an information container. As opposed to this, information embedding needs a carrier information entity in which the payload information will be embedded.
Packaging techniques: adding files with the information into simple archive packages such as bagit, zip and tar. Metadata files, such as METS and OAI-ORE, can be added to the archive packages. The ensures that the packaged objects can be restored so that the restored objects are identical to the original objects and that they can be verified by a checksum.
Embedding techniques: Making a distinction between the information that is the format of the item, and the message information which is embedded into the object itself. This includes: Digital Watermarking, Steganography (hiding messages), and attaching files or text to objects.
PeriCAT (PERICLES Content Aggregation Tool) is a framework that allows the encapsulation and decapsulation of information. (Decapsulation is the process to separate encapsulated entities from each other.) Each of the techniques have different features; the technique to be used should be chosen based on the specified requirements.